{"action":"Upgrade github.com/nats-io/nats-server/v2 to 2.1.9 or later.","affected":[{"fixed":"2.1.9","introduced":"0"}],"component":"github.com/nats-io/nats-server/v2","cve_ids":["CVE-2020-26521"],"ecosystem":"Go","epss":0.02157,"exploited":false,"fixed_versions":["2.1.9"],"ghsa_id":"GHSA-hmm9-r2m2-qg9w","id":"tcs_01M5KFCRQJPCZEFJ0NJQ1ENBYJ","modified_at":"2026-09-10T03:49:14.679744358Z","published_at":"2021-05-21T16:22:10Z","references":["https://osv.dev/vulnerability/GHSA-hmm9-r2m2-qg9w","https://github.com/nats-io/nats-server/security/advisories/GHSA-hmm9-r2m2-qg9w","https://nvd.nist.gov/vuln/detail/CVE-2020-26521","https://github.com/nats-io/jwt/pull/107","https://advisories.nats.io/CVE/CVE-2020-26521.txt","https://github.com/nats-io/nats-server","https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/VT67XCLIIBYRT762SVFBYFFTQFVSM3SI","https://www.openwall.com/lists/oss-security/2020/11/02/2"],"severity":{"label":"high","score":7.5},"sources":[{"source":"osv","source_id":"GHSA-hmm9-r2m2-qg9w","url":"https://osv.dev/vulnerability/GHSA-hmm9-r2m2-qg9w"}],"summary":"Nil dereference in NATS JWT causing DoS of nats-server"}